Did you know there is a spider whose brains spill into its legs, that some leeches have 32 brains and that the giant squid eats through its brain? Well then, head over to WebEcoist to learn more about the brains of 13 different creatures.

There is one thing that makes this a bad article and that's too much speculation.

That Dolphin's are self-aware is a contestable claim. It is popular for people to say that they are but that issue is still being debated, and rightly so, we don't even have a way of knowing if humans are self-aware. Or what do we even mean by self-awareness?

Self-awareness seems to be the generation and reflection on abstract and related concepts. Maybe Dolphin's can do this, maybe some humans can't, we just don't have a way of testing for self-awareness (or consciousness) but researchers are trying to come up with ways of determining whether or not a creature has the minimal neural correlates necessary for these processes. Christoph Koch, author of "The Quest for Consciousness" and Nobel Laureate and co-discoverer of the structure of DNA and author of "The Astonishing Hypothesis" Francis Crick spent decades trying to come up with the Neural Correlates of Consciousness (NCC) and have not been able to do so completely.

But the author of this article has the answers? Ok...

On another note: Besides brain-size there is also brain-density, and while it is common for researchers to examine the brain-size:body-size ratio, they almost always overlook the brain-density;body-size ratio.

There are [b]distinct[/b] differences in the male and female brains of humans. Those differences are also typically not brain-size differences but brain-density differences. The female brain has denser commissures (i.e. corpus callosum) and limbic tissue but the male brain typically has denser pareital cortices and some regions of the PFC. Behaviourally speaking this correlates with known differences in the psychology literature; boys are typically better with temporospatial orientation and can perform "mental object rotation" faster and more easily than girls, but girls tend to be more attuned to social cues. And so on and so forth...

Here's something: The first neuron's to ever be studied were giant neurons of the squid, because these are 0.5mm-1.00mm in size and can be easily studied. The smallest neuron size is like 0.004mm (4?m).

So I could have 250 of these 0.004mm neurons to every one of these 1mm neurons and I'd have the same "mass" but I'd have 250x the density in terms of nerve count.

This is a huge difference because I can't really do anything with one neuron, but with 250 I might be able to do something.

If the human brain has 100 billion nerve cells that are 0.004mm in size, but the sperm whale has - I don't know how much it has or what size - 40 billion neurons that are 1mm in size, then the whale brain will be 100 times larger than the human brain, but have probably 60% less computational power.